Cadmium telluride (CdTe) photovoltaics (PV) is a new and promising energy generation technology. However, such cadmium telluride photovoltaic modules may be characterized as hazardous waste because they contain a cadmium compound. Cadmium is a toxic element and tellurium is a rare one. Separating the two elements enables cleaning of hazardous waste streams and recovery of the valuable tellurium.
Photovoltaic modules at the end of their useful life have to be decommissioned and disposed of, or re-used in some way. Environmental regulations can impact the complexity and the cost of dealing with end-of-life photovoltaic modules. For example, the inclusion of spent photovoltaic modules with waste electric- and electronic-equipment under some European directives (e.g., Waste from Electric & Electronics Equipment (WEEE) and Restrictions on the use of certain Hazardous Substances (RoHS)) will impact cadmium telluride photovoltaic modules that contain lead and cadmium compounds, respectively.
Handling and disposing of spent modules and manufacturing scrap characterized as hazardous costs about twenty times more than dealing with non-hazardous waste. Recycling the semimetals such as tellurium from spent photovoltaic modules addresses this issue because the hazardous elements in a photovoltaic module typically are less than 0.1% of its mass.